Justice Cameron Mander handed down the sentence to a subdued but relieved courtroom.
Brenton Tarrant murdered 51 worshippers at Al Noor Mosque and Linwood Islamic Centre on 15 March, 2019. He also tried to kill dozens more.
It's the first time any judge has imposed a sentence of life without parole.
Justice Mander told Tarrant that his crimes were so wicked that being detained until he dies would not exhaust the requirements of punishment and denunciation.
He posed the rhetorical question - "if not here, then when?".
